Study shows old-school meds as effective as Enbrel

With Pfizer poised to hand off full promotional responsibilities for Enbrel to its partner Amgen, New England Journal of Medicine has published a study suggesting that the $4 billion RA drug may not be worth the premium price. Researchers found they could match Enbrel's effectiveness by combining sulfasalazine and hydroxychloroquine with methotrexate, which is a common RA therapy. They also compared this three-part combination to an Enbrel-methotrexate combination, which is not unusual.

The potential significance of the finding is fuzzy – an NEJM editorial noted that doctors tend to stick with what they know, and may not be willing to switch treatments because of the new data. Authors Joan Bathon and Donald McMahon note that this probably hinges on payer preference and that docs' comfort level with Enbrel could make the finding irrelevant.

This does not mean that doctors will go for just any biologic, and experts have said that RA biosimilars are going to have to fight for market share once the FDA gets the biologics look-alike market rolling, as the complexity of an RA biologic will give them pause about inexact replicas. Expectations are that less complex biosimilars will gain traction first, giving Amgen's Enbrel and AbbVie's Humira more time to ring up strong sales, even as patent protections disappear.
Yet this comparative stronghold doesn't mean these brands are impermeable – Pfizer has said in recent earnings calls that its RA drug Xeljanz has an increasing fan base among physicians, and news from Bristol-Myers Squibb Wednesday indicates that a head-to-head comparison between its drug Orencia and AbbVie's Humira shows the drugs, when paired with methotrexate, to be comparable.